Lots of Irish names have an 'O' at the beginning, like O'Reilly or O'Farrell. Why is this, does the O stand for something?|||In days of olde many people were named after their parents. Son of Brian became son O'Brien which later shortened to O.Brien|||absolutely. there are man examples of this: Van, Von, Mc, O, and even son as an ending. I have learned that all of theses equal the same meaning, which is "of". In your example, O'Reilly would mean "of Reilly" or "of Farrel" Usually dates back to a time where last name were not necessary. but when a man would have a child, then would name him "Garret O'Reilly" being that the fathers name was indeed Reilly. Obviously, this was much more popular with the Irish. hope i helped.|||I believe it literally means "descendant of", meaning that the patron of the lineage had the name that appears after the O. O'Conner folk are the descendants of someone named Conner way back down the line, that sort of thing.|||It doesn't stand for "of", its supposed to be written as 脫 and in Irish means "grandson of".
Ignore that stupid Sicilian troll.|||because irish people are drunks.|||It means "son of".
"Of" gets shortened to O'
In Scotland, Mac means the same thing, so Donald's son Fred would be Fred McDonald. In England he would have been Fred Donaldson.|||It is shorthand for "of".